A touch panel has a plurality of electrodes which are electrically insulated from each other. The touch panel is capable of detecting a contact position, where a detection target is in contact with a detection surface, by detecting a change in capacitance in an electrode which change is produced in a case where a finger or an input pen is brought into contact with a detection surface. Such electronic devices are widely used that a touch panel is provided on a display surface of a display device and that allows a user to input an operation via a display screen while the user is looking at a displayed image.
Further, there is known a touch panel which has two electrode layers provided on respective different plane surfaces and which detects a contact position of a detection target in accordance with a change in capacitance between an electrode provided in one of the two electrode layers and an electrode provided in the other of the two electrode layers.
In regard to such a technique, Patent Literature 1 discloses a touch panel having a conductive film for a touch panel which film is capable of suppressing occurrence of a moire even in a case where the conductive film is attached to a display panel of a display device. Patent Literature 2 discloses a conductive sheet suitable for use in a projected capacitive touch panel.
FIGS. 25 through 28 are views each for explaining a touch panel of Patent Literature 1. FIG. 25 is a cross-sectional view illustrating a layered conductive film. FIG. 26 is a plan view illustrating first conductive patterns formed in a first conductive film. FIG. 27 is a plan view illustrating second conductive patterns formed in a second conductive film. FIG. 28 is a plan view illustrating the layered conductive film in which the first conductive film and the second conductive film are combined.
The touch panel of Patent Literature 1 includes a layered conductive film 500. As illustrated in FIG. 25, the layered conductive film 500 is configured such that a first conductive film 510A is layered on a second conductive film 510B. The first conductive film 510A has a first transparent substrate 512A and a first conductive part 514A formed on a principal surface of the first transparent substrate 512A. The second conductive film 510B has a second transparent substrate 512B and a second conductive part 514B formed on a principal surface of the second transparent substrate 512B.
As illustrated in FIG. 26, the first conductive part 514A extends in an “m” direction in FIG. 26. The first conductive part 514A has (i) first conductive patterns 520A each made up of a thin metal line 516 and (ii) first auxiliary patterns 540A arranged around the first conductive patterns 520A.
Each of the first conductive patterns 520A is configured such that two or more first large grids 530A are connected to each other. Each of the first large grids 530A is configured such that two or more small grids 550 are combined.
As illustrated in FIG. 27, the second conductive part 514B extends in an “n” direction in FIG. 27. The second conductive part 514B has (i) second conductive patterns 520B each made up of a thin metal line 516 and (ii) second auxiliary patterns 540B arranged around the second conductive patterns 520B.
Each of the second conductive patterns 520B is configured such that two or more second large grids 530B are connected to each other. Each of the second large grids 530B is configured such that two or more small grids 550 are combined.
In a case where the first conductive film 510A is layered on the second conductive film 510B so as to form the layered conductive film 500, the first conductive patterns 520A and the second conductive patterns 520B are arranged so as to intersect each other, and the second large grids 530B of the second conductive film 510B are arranged so as to fill in gaps between the first large grids 530A of the first conductive film 510A.
In this case, when viewed from above, combination patterns 560 are formed by the first auxiliary patterns 540A facing the second auxiliary patterns 540B. As a result, when the layered conductive film 500 is viewed from above, the small grids 550 are laid all over as illustrated in FIG. 28. This causes boundaries, between the first large grids 530A and the second large grids 530B, not to be visible. Accordingly, visibility is improved.